The Miocene Marls of Cabezo Negro

 Cabezo Negro forms a volcanic structure (interpreted as the remnant of a lopolith-like volcanic conduit or a lava flow) that pierced the Upper Miocene sedimentary deposits and injected its magma into them.

These inclusions of Miocene marl are clearly visible at the highest point and along the edges of the outcrop. The volcanic rocks, the iconic lamproites associated with the deep-seated Socovos fault, emerged amidst these marly layers, creating a striking geological boundary where the light gray of the Tertiary marls bears witness to the original terrain pierced by volcanic fire 7 millions years ago.

(Source: Ayuntamiento de Calasparra)